"He has started developing a little more of an attitude recently to try to tell us when he doesn't like certain things," Duggar, 24, tells Us. "For the most part, as long as he is entertained, he stays happy."
The Jill & Jessa: Counting On star adds that her son generally has a "very sweet personality."
"He loves to be with people more than alone by himself, but if he has a clean diaper and full belly, he can entertain himself for awhile," continues the reality TV stalwart, who welcomed her bundle of joy with husband Derick Dillard in April 2015. The three of them currently reside in El Salvador, where Duggar and Derick are doing missionary work.
As far as which of his parents Izzy takes after most, the first-time mom says, "It's hard to tell who he will be most like as a kid, but as far as a baby, I'd say he is a lot like both of us, since from what I hear we were both pretty good babies."
Duggar says she is glad to be able to raise her son in Central America because it allows him "to experience different cultures at a young age." She adds that she frequently "can't help but think how cute he is."
"I also love watching him giggle any time we tickle his belly," the 19 Kids and Counting alum says. "He has such a cute big smile with slight dimples (from Daddy!) and big baby teeth. He melts our hearts!"
For more from Jill and younger sister Jessa Duggar about raising their first sons, pick up the new issue of Us Weekly, on stands now.
Jill & Jessa: Counting On's season 1 finale airs on TLC Tuesday, May 3, at 9 p.m. ET.
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